XML 52 R41.htm IDEA: XBRL DOCUMENT v3.8.0.1
Loss And Loss Adjustment Expense Reserves (Schedule Of Losses And Loss Adjustment Expenses) (Detail) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Loss And Loss Adjustment Expense Reserves [Line Items]    
Policyholder Benefits And Claims Incurred Net $ 72 $ 94
U S Public Finance Insurance [Member]    
Loss And Loss Adjustment Expense Reserves [Line Items]    
Policyholder Benefits And Claims Incurred Net 77 11
Second-Lien RMBS [Member]    
Loss And Loss Adjustment Expense Reserves [Line Items]    
Policyholder Benefits And Claims Incurred Net 2 23
First-Lien RMBS [Member]    
Loss And Loss Adjustment Expense Reserves [Line Items]    
Policyholder Benefits And Claims Incurred Net (12) 57
CDOs [Member]    
Loss And Loss Adjustment Expense Reserves [Line Items]    
Policyholder Benefits And Claims Incurred Net 5 2
Other [Member]    
Loss And Loss Adjustment Expense Reserves [Line Items]    
Policyholder Benefits And Claims Incurred Net [1] $ 0 $ 1
[1]
Includes non-U.S. public finance and other issues.